Apparatus for pumping liquid in the treatment of mineral ores



Nov. 28, 1933. H. w. B. GARDINER El AL 1,937,338

APPARATUS FOR PUMPING LIQUID IN THE TREATMENT OF MINERAL ORES Filed March 17, 1935 2 Sheets-Sheet l 5 Fig.1.

W /NgEA/Tms BY i ATTORNEY 1933- H. w. B. GARDINER ET AL 1,937,338

APPARATUS FOR PUMPING LIQUID IN THE TREATMENT OF MINERAL ORES Filed March 17, 1935 2 Sheets-Sheet 2 Fig.3. V|- J L I LII 8 O 11% 1 P f: 2% IVUU IV wvzwrom Maw AT ORA/E Patented Nov. 28, 1933 UNITED PA E T O F- C warm. (or 103721 This invention relates to the treatment of mineral ores, for example by froth flotation, cyani clation and the like processes, andmore particularly to apparatus. for feeding liquids, such as reagents,

' 6 during the treatment'of mineral ores.

i In such treatment it is often essential that the quantity of liquid being fed should be accurately known and that the quantity should be adjustable; One object of the present invention is to provide improved feeding apparatus in which this adjustment is easily effected. Another object is to prevent oil used for lubricating moving parts of the apparatus from coming in contact with the liquid'being fed. Many of the liquids used 16 carry matter in suspension and it is a further object of the invention toe'nsure that such liquids are agitated during feeding toprevent the matter from settling out;

W Apparatus for feeding liquids during the treat-- ZB'j-ment of mineral ores, (according to the present invention, comprises a .pump'adapted' to feed liquid from a'supply tank and meansadapted' to'be' adjusted to different positions to'vary the rate of feed, definite known quantities of liquid being fed for each of the positions of the said means. The liquid may be fed under pressure by the pump thereby ensuring that the rate of delivery is substantially independent. of the. viscosity of the liquid. Thus a definite volume. of 80 liquid may be Withdrawn from'the supply tank and a proportion of that volume may then be forced by the pump through the outlet or delivery valve of the pump, the said adjustablemeans 7 being adapted to vary the said proportion of the volume. 1 r

The pump may be adapted to force liquid back towards the supply tank and'the said adjustable means to vary the period during which the pump can force the liquid back. The adjustable means I 0 may vary the period during which the inlet valve to'the. pump is closed.

Conveniently the pump may draw liquid out of the supply tank and then tend to force it back again and the inlet valvewhen closed may prevent the return of the liquid to the tank and force it to flow through the outlet valve which may be biassed to the closed position. In such an arrangement the inlet valve may'comprise a' slide valve and the adjustable means may varyjthe point in the stroke of the slide at of the valve opening occurs.

The invention will now be' described byway of example, with reference to the accompanying drawings of pumping apparatus forfeeding liq 55 uids duringthe' treatment of mineral ores. Figwhich closing ure '1 of the drawings is a sideelevation of the apparatus; Figure 2 is a section through the casing on the line II II of Figure '1, Figure 3 isa section on the line IIIIII of Figure 2, the pointer (not shown in Figure 2') for indicating the rate of feed being shown broken away in parts to show details"ofconstruction; Figured is 'a sectio n 'on the line IVIV of Figure 3 and Figure 5' is a section on the line V V of Figure 3 with part broken away to shows. section on the'line.VI-'VI or Figure 3.. H As shown the apparatus comprises a compartment 4 containing the pump mechanismanda compartment 5 containing mechanism for operating the pump andcontrolling the rate of feed. The pump is provided with an inlet 1 which can be connected toithe supply tank and an outlet '2 to which the. delivering pipe is attach'edfThe pump is operated through a driving shaft 3 which is'rotat'ed at constantfspeed, for example by'fan' electric constantspeed' motor. Mounted on the outside of the compartment 5 is a pointer '6 which can be, moved over a scale 7 to adjust the rate at'which"the pump delivers liquid through the outlet 2, The pumping mechanism comprises two plunge I ers 8 and S'arrangedI to reciprocate respectively. in two vertical barrels 10' and 11 drilled out of a metalbodylZ; j'the plunger 9 and barrel 11 are of slightly larger diameter than 'the. 5 plunger 8 and barrel 10. The two barrels 10' and llareconnected together adjacent to their lowerends by a horizontal duct '13, whilst'the barrel 10' is also connected to the inlet lby a horizontal duct 14;. the plunger 8 reciprocating. in the barrel 10 thus forms an inlet valve for cutting off the communication between the ducts. 13 and 14. T The lower end of the barrel '11). is connected by a by-pass 1,5 to the duct 14, so that liqu'idtrapped in the lower end of the barrel 10 1 5 can escape into the ductf14 during the latter part of the down stroke of the plunger 8. The, plunger 9 reciprocating in the barrel 11 actsv as a pump for drawing liquid from the supply tank along'thefduct .14 into the duct 'lSand then 60 forcing it through a spring closed ball delivery or outlet valvefl'6 into a horizontal duct 17 lead ing to the outlet 2., 1 j The two plungers 8 and 9 areoperated from the same cam shaft 18 by means, of'cams 2 1 1 5' and 23 and rockers 22 and 24. 'The cam shaft 13' is arranged in the container 5 andj'i s" driven throughl worm reduction ge'aring. 1Q bylthe driving shaft, 3. Arranged in the 1 samel co'ntainer 5' is acrankedshaft 20 "on which the rockeis pipe to froth flotation cells.

22 and 24 of the two plungers 9 and 8 are pivotally mounted, the rocker 24 of the inlet valve plunger 8 only being mounted on the cranked valve plunger rocker 24 without" affecting the,

position of the pivoted point of the pump plunger rocker 22 and so varies the timing of the inlet valve to vary the rate of feed. The scale 7 over which the pointer 6 moves may be calibrated to indicate the volume of liquid being fed per minute, or the different positions on the scale may be numbered and the rate of delivery be obtained from a calibration chart.

One end of each rocker bears against one of the cams 21 and 23 mounted on the cam shaft 18 and is either pressed against the cam by means of a spring or, as shown, is positively coupled to the cam by a member 26 which embraces the cam. ,The cam 23 operating the valve plunger 8 leads the other cam 21 by approximately ninety degrees and, if desired, means may be provided for varying this lead thereby enabling the rate of feed to be varied by varying the timing of the inlet valve relatively to the pump plunger.

The other end of each rocker is coupled to the top end of its associated plunger by means of a horizontal pin 27 engaging a horizontal slot 28 in the top end of the plunger, in which slot the pin 27 is free to slide horizontally. The

compartment 5 containing the pump operating mechanism is partly filled with oil for lubricating the moving parts of the mechanism and a partition 29 is arranged between the two compartments to prevent oil getting into contact with the liquids being pumped. The rockers 22 and 24 are suitably shaped to pass over the top of this partition through slots 30 to their respective plungers.

The compartment a containing the pump mechanism is removably attached to the other compartment 5 by means of a spindle 31 projecting horizontally from the latter compartment 5 and to which the former compartment 4.- is secured by means of a screw 32 having a milled edge. The pumping mechanism can thus be easily removed for cleaning purposes by removing the milled screw 32 and sliding the top ends of the plungers clear of the pins 27 on the rockers. Furthermore the part containing the inlet and outlet 1 and 2 may be removed in a similar manner from the compartment 4 by removing a milled screw 33.

.In operation the inlet 1 is connected to a supply tank containing'liquid which it is required to feed in definite known quantities for the treatment of mineral ores, for example the liquid may be froth flotation reagents and the pump may serve to feed it through the delivery The pointer 6 is then set to the quantity which it is desired to deliver per minute and the motor driving the pump is started up. When the plunger 9 rises in the barrel l1, liquid is drawn into the duct 13 and barrel 11 past the inlet valve. the plunger 9 commences to descend again it forces this liquid back along the supply pipe towards the supply tank until the inlet valve closes, since the head of liquid is not sufficient to open When the outlet valve 16 against the pressure of the valve spring. When however the inlet valve is closed by the descending plunger 8, which is ninety degrees ahead of the plunger 9, the descending plunger 9 forces the liquid entrapped in the duct 13 and barrel 11 through the outlet valve 16 to the outlet 2 until the inlet valve is again opened by the plunger 8 rising.

Itwill thus be seen that during each cycle of the plunger 9 a definite quantity of liquid is forced through the outlet valve dependent on the portion of the cycle during which the inlet valve is closed, so that the rate of feed may therefore be varied by varying the portion of the cycle during which the inlet valve is closed by rotating the cranked shaft 20 by means of the pointer 6 to raise or lower the pivoted point of the rocker 24 to vary the distance the plunger 8 slides past the valve opening. The scale 7 may be calibrated, fork example in cubic centimetres per minute, so that for any position of the pointer 6 on the scale '7 the 'pump feeds liquid at a definite and known rate, which is substantially independent of the viscosity of the liquid. This definite calibration is possible owing to the liquid being fed through the outlet valve under pressure, instead of by the'usual form'of gravity feed in which the liquid is allowed to drip.

Many of the liquids used, and more particularly some of the reagents used in froth flotation processes contain matter in suspension, and it will be seen that in the arrangement described above some of the liquid is pumped back along the supply pipe so that a surge is set up and the liq-' containing pump mechanism which is 'coated' with one reagent may be removed in the manner hereinbefore described, and the spare clean pump mechanism inserted in its place for pumping another reagent. Owingto the simple construction of the pump mechanism it may easily be cleaned, whilst it is unnecessary to clean the mechanism in the other compartment since this does not come in contact'with the liquid being fed.

When feeding liquids carrying a large quantity of matter in suspension it may be found that the outlet valve is liable to become clogged, in which case this valve may be replaced by a slide valve operated by the cam shaft in a similar manner to the inlet valve.

If the pump is to be used for pumping liquids of a corrosive nature it is necessary to form .those parts of the pump which come in contact with the liquid, of a non-corrosive material. the plungers 8 and 9 maybe made of stainless steel or of ordinary steel coated with a suitable ebonite-like material, Whilst the body 12 may be made of non-corrosive alloy, or of any suitable metal and the barrels and ducts lined with a suitable ebonite-like material, or the entire body may be made of ebonite-like material. A suitable ebonite-like material which may be used is the material known as Dexonite.

We claim:-'-

1. Apparatus for pumping liquids in the treatment of mineral ores comprising a compartment providing an oil bath, a plunger-block on the outside of said compartment having bores in which -1 Thus g a pump plunger and a slide valve reciprocate, a pair of rocker arms pivotally mounted within said compartment and extending through a wall thereof for reciprocating said plunger and the slide valve, means in said compartment for rock-' ing said rocker arms in predetermined sequence, fulcrums upon'which the respective rocker arms are pivoted, the fulcrum for the rocker arm of said valve being formed as a crank on a rod rotatably mounted in and projectingthrough a wall of said compartment, an operating arm forming a pointer mounted on said crank rod outside of the compartment for rotating the rod to vary theposition of said crank fulcrum relative to the fulcrum of the plunger rocker arm and a scale cooperating with said pointer arm for indicating the position of said' fulcrum crank.

2. Apparatus for pumping liquids in the treatment of mineral ores comprising a plunger-block provided with bores in which a pump plunger and a slide valve respectively are arranged to reciprocate, a compartment having means therein for reciprocating said plunger and the slide valve in predetermined sequence, said means including rocker arms extending through the wall of 

